The flying-wing aircraft is an innovative design that seamlessly integrates the wing and fuselage, offering improved aerodynamics and fuel efficiency. However, due to changes in layout and control surfaces, its attitude control has undergone significant changes. In this paper, the attitude control methods with different control allocation strategies are investigated. Based on a newly developed flying-wing UAV, systematic wind tunnel free flight tests are conducted. Compared with the split-drag-rudder alone, the results show that the addition of differential thrust of electric ducts can effectively enhance heading control capability. The degradation of the stealth performance due to pre-opening of the split-drag-rudders can thus be avoided. Meanwhile, the elevons exhibit a close tracking in different roll and pitch attitude commands, presenting a good performance in both dynamic and steady-state responses.